123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199 |
- /* Copyright (C) 2014 Stony Brook University
- This file is part of Graphene Library OS.
- Graphene Library OS is free software: you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public License
- as published by the Free Software Foundation, either version 3 of the
- License, or (at your option) any later version.
- Graphene Library OS is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU Lesser General Public License for more details.
- You should have received a copy of the GNU Lesser General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>. */
- /*
- * shim_sched.c
- *
- * Implementation of system calls "sched_yield", "setpriority", "getpriority",
- * "sched_setparam", "sched_getparam", "sched_setscheduler", "sched_getscheduler",
- * "sched_get_priority_max", "sched_get_priority_min", "sched_rr_get_interval",
- * "sched_setaffinity", "sched_getaffinity".
- */
- #include <api.h>
- #include <errno.h>
- #include <linux/resource.h>
- #include <linux/sched.h>
- #include <pal.h>
- #include <shim_internal.h>
- #include <shim_table.h>
- int shim_do_sched_yield(void) {
- DkThreadYieldExecution();
- return 0;
- }
- /* dummy implementation: ignore user-supplied niceval and return success */
- int shim_do_setpriority(int which, int who, int niceval) {
- __UNUSED(who);
- if (which != PRIO_PROCESS && which != PRIO_PGRP && which != PRIO_USER)
- return -EINVAL;
- if (niceval < 1 || niceval > 40)
- return -EACCES;
- return 0;
- }
- /* dummy implementation: always return the default nice value of 0 */
- int shim_do_getpriority(int which, int who) {
- __UNUSED(who);
- if (which != PRIO_PROCESS && which != PRIO_PGRP && which != PRIO_USER)
- return -EINVAL;
- return 20; /* default nice value on Linux */
- }
- /* dummy implementation: ignore user-supplied param and return success */
- int shim_do_sched_setparam(pid_t pid, struct __kernel_sched_param* param) {
- if (pid < 0 || param == NULL)
- return -EINVAL;
- return 0;
- }
- /* dummy implementation: always return sched_priority of 0 (implies non-real-time sched policy) */
- int shim_do_sched_getparam(pid_t pid, struct __kernel_sched_param* param) {
- if (pid < 0 || param == NULL)
- return -EINVAL;
- param->__sched_priority = 0;
- return 0;
- }
- /* dummy implementation: ignore user-supplied policy & param and return success */
- int shim_do_sched_setscheduler(pid_t pid, int policy, struct __kernel_sched_param* param) {
- policy &= ~SCHED_RESET_ON_FORK; /* ignore reset-on-fork flag */
- if (pid < 0 || param == NULL)
- return -EINVAL;
- /* fail on unrecognized policies */
- if (policy != SCHED_NORMAL && policy != SCHED_BATCH && policy != SCHED_IDLE && /* non-real-time */
- policy != SCHED_FIFO && policy != SCHED_RR /* real-time */)
- return -EINVAL;
- /* non-real-time policies must have priority of 0 */
- if ((policy == SCHED_NORMAL || policy == SCHED_BATCH || policy == SCHED_IDLE) &&
- (param->__sched_priority != 0))
- return -EINVAL;
- /* real-time policies must have priority in range [1, 99] */
- if ((policy == SCHED_FIFO || policy == SCHED_RR) &&
- (param->__sched_priority < 1 || param->__sched_priority > 99))
- return -EINVAL;
- return 0;
- }
- /* dummy implementation: always return SCHED_NORMAL (default round-robin time-sharing policy) */
- int shim_do_sched_getscheduler(pid_t pid) {
- if (pid < 0)
- return -EINVAL;
- return SCHED_NORMAL;
- }
- int shim_do_sched_get_priority_max(int policy) {
- /* fail on unrecognized policies */
- if (policy != SCHED_NORMAL && policy != SCHED_BATCH && policy != SCHED_IDLE && /* non-real-time */
- policy != SCHED_FIFO && policy != SCHED_RR /* real-time */)
- return -EINVAL;
- /* real-time policies have max priority of 99 */
- if (policy == SCHED_FIFO || policy == SCHED_RR)
- return 99;
- /* non-real-time policies have max priority of 0 */
- return 0;
- }
- int shim_do_sched_get_priority_min(int policy) {
- /* fail on unrecognized policies */
- if (policy != SCHED_NORMAL && policy != SCHED_BATCH && policy != SCHED_IDLE && /* non-real-time */
- policy != SCHED_FIFO && policy != SCHED_RR /* real-time */)
- return -EINVAL;
- /* real-time policies have min priority of 1 */
- if (policy == SCHED_FIFO || policy == SCHED_RR)
- return 1;
- /* non-real-time policies have min priority of 0 */
- return 0;
- }
- /* dummy implementation: always return 100 ms (default in Linux) */
- int shim_do_sched_rr_get_interval(pid_t pid, struct timespec* interval) {
- if (pid < 0)
- return -EINVAL;
- if (test_user_memory(interval, sizeof(*interval), true))
- return -EFAULT;
- interval->tv_sec = 0;
- interval->tv_nsec = 100000000; /* default value of 100 ms in Linux */
- return 0;
- }
- static int check_affinity_params(int ncpus, size_t len, __kernel_cpu_set_t* user_mask_ptr) {
- /* Check that user_mask_ptr is valid; if not, should return -EFAULT */
- if (test_user_memory(user_mask_ptr, len, true))
- return -EFAULT;
- /* Linux kernel bitmap is based on long. So according to its
- * implementation, round up the result to sizeof(long) */
- size_t bitmask_long_count = (ncpus + sizeof(long) * 8 - 1) / (sizeof(long) * 8);
- size_t bitmask_size_in_bytes = bitmask_long_count * sizeof(long);
- if (len < bitmask_size_in_bytes)
- return -EINVAL;
- /* Linux kernel also rejects non-natural size */
- if (len & (sizeof(long) - 1))
- return -EINVAL;
- return bitmask_size_in_bytes;
- }
- /* dummy implementation: ignore user-supplied mask and return success */
- int shim_do_sched_setaffinity(pid_t pid, size_t len, __kernel_cpu_set_t* user_mask_ptr) {
- __UNUSED(pid);
- int ncpus = PAL_CB(cpu_info.cpu_num);
- int bitmask_size_in_bytes = check_affinity_params(ncpus, len, user_mask_ptr);
- if (bitmask_size_in_bytes < 0)
- return bitmask_size_in_bytes;
- return 0;
- }
- /* dummy implementation: always return all-ones (as many as there are host CPUs) */
- int shim_do_sched_getaffinity(pid_t pid, size_t len, __kernel_cpu_set_t* user_mask_ptr) {
- __UNUSED(pid);
- int ncpus = PAL_CB(cpu_info.cpu_num);
- int bitmask_size_in_bytes = check_affinity_params(ncpus, len, user_mask_ptr);
- if (bitmask_size_in_bytes < 0)
- return bitmask_size_in_bytes;
- memset(user_mask_ptr, 0, len);
- for (int i = 0; i < ncpus; i++) {
- ((uint8_t*)user_mask_ptr)[i / 8] |= 1 << (i % 8);
- }
- /* imitate the Linux kernel implementation
- * See SYSCALL_DEFINE3(sched_getaffinity) */
- return bitmask_size_in_bytes;
- }
|